<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>

<body>
  <input type="text">
</body>
<script>
  const input = document.querySelector('input');
  //input.addEventListener('keydown', (event) => {
  //  console.log(event.key); // 按下的键
  //})
  //input.addEventListener('keyup', (event) => {
  //  console.log(event.key); // 按下的键
  //})


  //用户输入文本事件
  input, addEventListener('input', (e) => {
    console.log(input.value)
  })
</script>

</html>